Monday, June 30, 2014

Welcome to the twenty-sixth issue of LLVM Weekly, a weekly newsletter
(published every Monday) covering developments in LLVM, Clang, and related
projects.
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Trail of Bits have posted a preview of
McSema, a
framework for translating x86 binaries to LLVM bitcode. The accompanying talk
took place on the 28th June, so hopefully we'll hear more about this soon. The
blog post tells us that McSema will be open source and made available soon.

LLVM commits

A significant overhaul of how vector lowering is done in the x86 backend has
been started. While it's under development it's off by default, though it's
hoped that in times there will be measurable performance improvements on
benchmarks conducive to vectorization.
r211888 and more.

X86 FastISel will use EFLAGS directly when lowering select instructions if
the condition comes from a compare. It also now supports floating-point
selects among other improvements. r211543,
r211544, and more.

ScaledNumber has been split out from BlockFrequencyInfo into the Support
library. r211562.

The loop vectorizer now features -Rpass-missed and -Rpass-analysis
reports. r211721.

The developer documentation has been updated to clarify that although you
can use Phabricator to submit code for review, you should also ensure the
relevant -commits mailing list is added as a subscriber on the review and be
prepared to respond to comments there.
r211731.